¶ … Rene Descartes wrote "I think therefore I am," philosophers have considered the meaning, origin, and function of cognitive thought (Newman, 2014). Thinking in itself appears to be proof of one's own existence. Self-consciousness -- the awareness that one is thinking -- offers indelible proof of a higher order of thought. Yet paradoxically, thoughts also seem to arise seemingly unbidden from the recesses of the mind. The sources of thought have been attributed to everything from God to nothingness (Hauser, 2009). Moreover, the sources of individualized thought processes are related to socialization and acculturation as well as to innate sensations and belief systems. There are some trends of human cognition that may be universal, and others that are instilled through social norms. Understanding the ways thought processes work is one of the most important aspects of being human. "Thinking is the extraordinary process we use every waking moment to make sense of our world and lives," (Chaffee, 2004, p. 2). Faulty thinking can lead to problems ranging from mental illness and miscommunications to superstition and logical fallacy. Clarifying one's thought processes can eliminate or minimize problems. Furthermore, understanding more about the origin of thought processes can help to reduce interpersonal friction because the more we recognize the origin of our own beliefs, the more we can see that others likewise developed their beliefs from their families or cultures.

As Engel (2000) points out, language may be a source of thought and feeling as well as the means of expressing those thoughts and feelings. Research into linguistics and the diversity of cultures reveals astonishing connections between the ways people conceptualize reality through language and the ways people think about the world. "Thought is actually shaped by the language in which it is conducted," (Engel, 2000, p. 61). Because language is intimately tied to culture, it is clear that culture and socialization is one of the most important, if not the single most important, influence on thought and emotion. The differences between individuals is therefore due more to nurture than to nature, more to environment than to individual biology. It is not that there is no absolute reality, but that perceptions of that reality vary so widely as to make it appear that there can be little common ground.

Strong opinions and beliefs are thoughts that have become linked to feelings or emotions, showing also that reasoned thinking and emotional sensations are connected. Descartes could have just as well said, "I think, therefore I feel." B.F. Skinner's (1989) research on human psychology shows that behaviors are linked to thoughts and feelings that have become internalized, which is why it becomes critical to examine the root thoughts and feelings before engaging in a process of behavioral change. While the internalization or automation of thought has a valid function in that it makes our lives efficient, there are certainly drawbacks to operating reflexively. As Chaffee (2004) points out, the "examined life" is one that can be more productive and fruitful than a life that is lived unconsciously. Bad habits and other destructive behaviors may be traced to faulty thoughts or irrational emotions. The essence of cognitive-behavioral and other psychological therapies is that changing one's thoughts can lead to shifts in feeling and behavior. The practice of mindfulness can reveal patterns of thought that give rise to uncomfortable emotions or irrational behaviors.

The sources of the ways I personally think and feel include brain chemistry, genetics, personality, socialization, and culture. The nature versus nurture debate pertains to sources of thought because each person does think or feel according to both environmental factors like culture, and to individual differences due to brain chemistry or personality. I believe that both nature and nurture are responsible for generating my own thoughts and feelings. This is why my siblings might think and feel differently from me: they had the same environmental exposures as I did in terms of parental and societal influences. Yet my siblings think and feel differently because they are also wired differently.

Because each person has a unique set of worldviews and beliefs, it may be tempting to believe that reality is relative. In other words, no convincing "absolute" reality seems to exist. It is far more likely that everyone looks at reality from a different angle, but that the reality itself is a shared one with a concrete and absolute truth to it. If there were no concrete and absolute truth, then science would not be a valid human endeavor. As it stands, science exists to show that absolute measurements point to the only immutable truth. Feelings and perceptions might be fleeting and variable, but measurable facts are not. I might feel shocked or opposed to something I read about, but if it is a proven fact, then I do need to acknowledge that...

This is why many atheists have trouble with religion. Essentially, religious people base their claims on feelings, thoughts, or worldviews that are not grounded in fact. Atheists cultivate science-based viewpoints that stress absolute reality over emotionality. Knowing that there may be different ways of viewing reality, it is important to ground what I say I "know" in the language of science and/or math. The observable measures of reality are ones that can be communicated to people with different points-of-view.