A Treatise of Human Nature is not only David Hume’s first philosophical work, it is also his most comprehensive execution of his massive contribution to the pursuit of human wisdom. Since its surprisingly tepid response from readers of the original edition, Hume’s work has justifiably come to be regarded as one of the most significant works in the history of philosophy. In his Treatise of Human Nature, David Hume delineates his theory of human morality. The form of argument Hume takes is the concept that human morality is not based on coherent thought and logical reason, but is instead the upshot of humanity’s passionate fervor. Since this fervor cannot present itself as the creation of logical reason, it would be consequently be the ultimate in the lack of logical thinking to adjudicate any moral deed as being the result of either rational or irrational thought. Hume delivers a succession of explanations that serve to reveal why humanity should express scepticism toward any conclusion based upon reasoning that is arrived at through familiarities based on sensory perception. Hume concludes that even in the face of complexities that are presented by virtue of the illogic inherent in sensory perception, humans still maintain a forcible belief in illogical conclusions due to psychology. This presents the paradoxical notion that strong belief is often grounded in contradictions.
Hume’s argument posits that it is even within the realm of possibility that the most grounded and confident reasonable conclusions are, in fact, merely probable and that the degrees of probability are subject to intense scrutiny with each additional analysis. Mistakes made on the basis of supposedly rational certainty are legion due to the inescapable imperfectability of human judgment. The ironic paradox of human judgment resides in the fact that each further analysis of the previous judgment decreases the probability of correctness in the original judgment. This has particularly chilling aspects when considered against the potential for reductions of probability in those elements that humans invest the utmost confidence in regarding the infallibility of correctness, such as laws of mathematics and science.
Hume emphasises that there are three stipulations required to confirm merely through observation. The first he termed the aspect of constant conjunction, in which the cause and the effect are required to be both spatially and constantly extant. The second stipulates that the cause must have come before the effect itself. And finally, there must be a connection of necessity; that is it must be possible to ascertain why the cause produces the effect. Hume’s appraisal of causation necessarily dictates that it can only be inferred and not examined and his conclusions indicate that it is impossible to achieve an impression of a necessary connection; rather, one must experience constant conjunction and temporal priority: “Experience only teaches us how one event constantly follows another, without instructing us in the secret connection which binds them together” (Hume, 1870, p. 347). Ultimately, Hume asserts that there are significant limitations to reason.
Hume maintains that humans remain convinced that any object that is observed exists independently. Once this belief is subject to analysis, however, it is determined to be without basis and that paradox provides a basis for conflict in the process of reasonable determination. All perceptions are dependent upon human observation and even the slightest modification in the senses can distort that perception. Since this is one of the few absolute truths that exists, it is not logical to assume that perception can be something existing independently of us, nor can it possibly exist when there is nobody there to perceive it. Despite this Hume asserts that people will almost never surrender their natural belief in the existence of an external world that is separate from their perceptions. The argument of the bases for scepticism point toward the idea that Hume believes that scepticism itself is actually outside the realm of the possible due to the compulsion of natural belief: “Nature, by an absolute and uncontrollable necessity has determined us to judge as well as to breathe and feel.” Nature compels humanity to acknowledge certain views even in the face of evidence to the contrary. The science of philosophy would potentially serve to make everyone utterly sceptical about the condition of the objects that are sensorily perceived if it were not for the fact that societal scepticism thwarts people from taking any philosophical argument too solemnly.
Hume’s dispute centers on the theory that it is impossible to think of a necessary connection through observation and that the concept one has of necessary connection occurs thusly. One experiences a steady concurrence of events A and B or repeated sense experiences where events resembling A are always followed by events resembling B. This manufactures a habit so that at any future appearance of A, one quite naturally expects B to follow. This, in turn, produces an internal feeling that passes from one thing another which in turn creates the sense from which the idea of necessary connection is drawn. A widespread but mistaken belief surrounding this topic is that necessity exists in the objects themselves. Hume explicate this erroneous belief by the natural tendency one possesses to accredit subjectively apparent qualities to objects.
There are chains of cause that lead to every effect, whether or not they can be discovered they are presumed to exist. Along with contiguity is the concept of progression. The reason is obliged to precede the effect. An object can be contiguous and occur prior to another without being its cause, a necessary connection between the two need to be established. The relation of cause to effect does not depend on the known qualities of objects, but instead on the ideas of contiguity and succession, which are imperfect. Hume refutes the definition of cause as something productive of another, because reason and production are synonymous, and thus one definition using the other is circular. Hume questions why it is necessary that everything whose existence has a beginning, should also have a basis. He also questions why particular causes are required to have such particular effects, and why is an inference drawn from one to the other. The statement that whatever has a beginning has also a cause of existence is not implied by any of the relations of resemblance, proportions in quantity and number, degrees of any quality, or contrariety; therefore, it is not able to be refutable using reason. Using that logic states that everything that exists should have a beginning, thus needing a cause. If it didn’t have a basis then it would have had to produce itself, and that logic would mean that it had to exist before it existed. That argument contradicts itself, because it uses itself as a basis for existence in its premise, when it is proving the concept of cause being a necessity. Consequently, it begs the question to prove cause and effect by relying on the conclusion to prove the premise. The ideas of cause and effect cannot vary too far from actual intuitions of the mind or ideas from the memory. One must first establish the existence of causes before one can infer effects from them. One have only two ways of doing that, either by an immediate perception of our memory or senses, called impressions, or, by an inference from other reasons, called thoughts. Regardless of the source of the feeling, the imagination and perceptions of the senses are the foundation for the reasoning that traces the relation of cause and effect. The inference that one draw from cause to effect does not come from a dependence on the two concepts to each other or from a rational objective look at the two. One object does not imply the existence of any other. All distinct ideas are separable, as are the ideas of cause and effect. The only way that one can infer the existence of one object from another is through understanding. Contiguity and succession are not sufficient to make us pronounce any two objects to be cause and effect, unless one perceive, that these two relations are preserved in several circumstances. Instances of which a person have had no familiarity, must resemble those, of which one has had experience.
There is a transition from impression to plan, with the necessary connection possibly depending on the inference, instead of the inference depending on the necessary connection. The only connection or relation of objects, which can lead us beyond the immediate notions of our memory and senses, is that of cause and effect, because a person can base one inference from an object to another. The concept of cause and effect comes from past knowledge that informs us that some particular objects are conjoined with each other. There is, however, debate over whether a necessary connection exists between cause and effect. If cause and effect are connected, there should be a reason, or necessity for their connection. All of our thoughts are formed from impressions, consequently there must be an intuition that forms the conception of necessity, if there really is such an idea. The basis of necessity lies between cause and effect, therefore that is where the focus should turn. When two objects are presented before us, one cause the other effect, no tie will ever be perceived uniting the two. All ideas are founded in impressions. The necessary connection between causes and effects is the foundation of the inference from one to the other.
Nevertheless, necessity only exists in the mind, not in physical material objects. The inspiration of the connection arises from the repetition of their union. That repetition doesn’t change anything in the objects, or make them relate to each other, it only affects the mind. There are two definitive definitions of causality that Hume finally attains. He views them as either an object precedent and contiguous to another, where all the objects similar to the former are placed in a like relation of priority and contiguity to those objects that resemble the latter. The other definition can be viewed as an object precedent and contiguous to another, and thus combined with it in the imagination, so that the conception of the one determines the mind to form the thought of the other, and the feeling of the one to form a more lively inspiration of the other. Hume sees the second definition of cause as being more accurate. The precedent and contiguous object seems to cause the effect, but in reality cannot be used to reason a necessary connection between cause and effect. The ideas of cause and effect, though they may be real, can only be supported by experience. David Hume’s argument in his epistemology on impressions and ideas mirrors his argument on causation. He looks at many of the same concepts, including contiguity, succession, and resemblance. Many of his arguments on causation refer back to the epistemology, concerning the connection between feelings and conceptions, as well as memory and the imagination. After comparing the two arguments there is only one rational end that you can come to, with the arguments being founded on the same premises and not contradicting each other, if you accept one, you must accept the other. Perceptions that enter the body with force form intuitions, including sensations, passions and emotions.
Those impressions are formulated in the composition of ideas. Impressions and conceptions can be broken down into easy and complex. Straightforward perceptions or thoughts admit of no distinction or separation, where complex can be divided into parts. Ideas are solely formed from impressions, and cannot be separated from those impressions. Ideas and impressions always correspond to each other. You can, however, have complex thoughts of which you never had impressions that corresponded to them in the same order. Therefore, you can imagine all sorts of things that you have never seen, such as the golden mountain. Whenever a person thinks of something such as this they enjoin two separate and unswerving ideas that the have been presented with formerly and separately. Though there is a great resemblance between complex impressions and ideas, it can be safely assumed they are not exactly the same at all times. Effortless impressions, on the other hand, always form simple ideas that resemble them. The idea can differ in degree from the impression, but not in nature. If undemanding ideas and impressions resemble each other, and complex ideas are formed from simple ones, then easy and complex are exactly correspondent. Ideas are preceded by other more lively perceptions, from which they are derived, and which they represent. Simple impressions are prior to their correspondent ideas. There can be certain impressions, however, that can be preceded by ideas, as in the case of reflection. An impression can strike the senses, and a copy of it taken to the mind, which will remain even after the impression ceases. It forms a lasting idea. The memory and imagination copy that impression and make it into an idea that can eventually give rise to other impressions and ideas, making for an exception that still does follow the rules of impressions and ideas. There are forces that cause ideas to be associated with each other. They arise from resemblance, contiguity in time and place, and cause and effect. Hume’s doctrine on causality follows many of the same ideas through the process of his epistemology, as does his definition of causality in his section on knowledge and probability. The first of the similarities lies with contiguity. Impressions and ideas are related, just as cause and effect are thought of as being related. There is also a perceived succession in both cases. Impressions precede ideas, just as a cause precedes effect. Even in the case of reflection, where a pre-conceived idea of the mind is there and can form other impressions, the initial impression comes before the idea. The concept of the impressions of the mind is one of the key pieces that associates Hume’s epistemology and his argument on causation. Cause and effect are complex and distinct ideas of the mind that are spawned from impressions. Ideas are separable, therefore cause and effect are not necessarily associated. The ideas of cause and effect are contingent upon Hume’s concept of impressions from his epistemology.
Those impressions were formed from perceptions of relations between cause and effect, which are based on knowledge. Impressions, in essence, formed the idea of a necessary connection between cause and effect. Impressions are based on understanding, and the impression that formed the idea of a necessary relation between cause and effect was no different. The only reason for the idea of cause and effect being related was a previous experience, or custom that tied cause and effect together. Hume’s doctrine on causality is firmly founded in the concepts from his epistemology. His theories on the relation between impressions and ideas tie in directly with his idea of a necessary connection between cause and effect. People have internal impressions that form the ideas of necessity, and those ideas are based on repetition and resemblance, but do not prove the claim that there is a necessary connection between cause and effect. Ideas are not original, they are formed from impressions and influenced by resemblance, and experience. Cause is not an original idea, it is formed from impressions, which are in turn formed from experience. Thus, we accept the idea of cause not because it is rational or well reasoned, but because of custom. Hume’s position is consistent, and ultimately if you accept his epistemology, you must accept the reasoning behind his ideas on cause and effect.
