The terms “Theism” and “theist” do not mean simply “Belief in God” and “believer in God” – although they do imply belief in God.
In general Theism implies three types of belief:
First, belief that there exists a single God who has some important characteristics, such as, for instance, he is personal and eternal and has an infinitely great amount of power, knowledge, wisdom and goodness;
Second, belief that this God created everything else there is and that his will to create the world is sufficient explanation for the existence of anything in created reality, including man (human beings);
Third, belief that this God, having created the universe, sustains it through his providence, and, when he deems necessary or opportune, interferes in the universe he created, through miracles (violation or suspension of the laws of nature), special revelations (made to specific individuals of his personal choice, such as, for instance, prophets, through which he lets man know of his plans and his will), response to prayers (which he indeed listens to, even if he does not respond favorably), etc.
This definition of “Theism” applies equally well to Judaism, Christianity, and Islamism – although each of these monotheistic religions differs from the others on a number of issues, in special with regard to the issue of God’s providence and, within it, the issue of his special revelations: what their content is, where, when and to whom they were made, etc.
This means that there can be Jewish, Christian and Muslim Theists. Each one accepts the special revelations sanctioned by their religion: the Jews, the Jewish Scriptures; the Christians, the New Testament (and, to some extent, the Jewish Bible, renamed the Old Testament); and the Muslims, basically the Koran. Christians and Muslims may accept parts of the special revelations received by the previous religions to the extent that they fit into their own revelations.
(Christians accept parts of the Jewish Scriptures, for instance. Very conservative or fundamentalist Christians may object to my saying they may accept “parts” of the Jewish Scriptures. They normally assert that they have to accept all of what the Old Testament contains. But this question, if it is parts or all, is not really relevant here.)
One of the most complicated issues in Theism has to do with how the theist came to know these three propositions that command his belief – what is the source and the justification of the propositions in which he believes – believing being the psychological act of accepting as true or at least reasonable the content of these propositions on the basis of some sort of evidence or accreditation process or procedure?
One type of answer starts from the fact that we, human beings, are built with the capacity to observe things with our sensory or perceptual apparatus, are able to think about what we observe, reflect about it, analyze it, organize it, draw preliminary conclusions, compare our preliminary conclusions with those of other human beings, discuss their merits, depurate them, combine the best ones into more complex views, systematize these views, test them against what we continue to observe in reality, etc. On the basis of this process some people come to conclude that the three propositions – or, at the very least, the first two – are true, or at least reasonable, given their comparison with alternative points of view.
Those who think along this line are convinced that using only the natural characteristics with which we are born we can go fair in explaining and justifying our acceptance of the three propositions that define Theism – or, at least, two thirds of them (the first two beliefs). The natural characteristics with which we are born, and that are relevant here, include our sensory or “perceptual apparatus” and our “mind”, which involves our capacity to think, reflect, compare, differentiate, integrate, abstract, generalize, infer, ratiocinate, etc., capacity generally labelled our “reason”, or our rational apparatus.
(Our mind has other capacities besides to think, etc., such as, the capacity to feel, the capacity to will, which involves choosing, deciding and acting, etc. Traditionally, our mind was said to include three “faculties”: thought, emotion and will. David Hume’s Treatise of Human Nature is divided into three “Books”, named “Of the Understanding”, “Of the Passions”, and “Of Morals” (which deals, this third one, with the will, which includes choice, decision and action.)
Without conceding that this line of reasoning is sufficient and adequate to support Theism, it is necessary to make a few considerations about the third proposition, the one that makes reference to communication between God and human beings, special revelations, miraculous interferences in the created world, etc. In a word: about Providence.
The terms “Deism” and “deist” include, as part of their meaning, basically the first two beliefs of Theism and the theist, namely:
First, belief that there exists a single God who has some important characteristics, such as, for instance, he is eternal and he has an infinitely great amount of power, knowledge, wisdom and goodness;
Second, belief that this God created everything else there is and that his will to create the world is sufficient explanation for the existence of anything in created reality, including human beings.
For Deism and the deist these two beliefs are fully rational, that is, their truth can be determined by man simply through the use of his perceptual and rational capacities – they do not depend on God’s revelation.
In general Deism and the deist stop here. The do not accept the third belief, that includes belief in Providence and, within Providence, special Revelation. For them, God created the world with everything that the world needed to operate (the laws of nature), without any need of God sustaining it after its creation. That is why the deist God is sometimes considered, by theists, a deus ex machina, a God that stays outside and away of the machine he created, the world. That is why the deist God is not personal in the sense that the theist God is: he does not interfere in his creation through miracles, he does not make special revelations through prophets (or other people), he does not listen and respond to prayers, etc.
Deism is, therefore, in a way, a “cleaner view” of Theism.
3. Hume, Theism and Deism
The eighteenth century – the century of Reason, the century the Lights, the century of the Enlightenment, the century of Immanuel Kant’s sapere aude – is the time in which Deism became popular and deists proliferated.
But the eighteenth century is also the century of David Hume and his skepticism. He was an empiricist, a naturalist, and a skeptic. He criticized the rational foundations of science (with his criticism of the notion of cause and the concept of induction), the rational foundations of ethics (with his assertion that reason does not move the will, because it is, and ought to be, the slave of our passions, which alone can move our will and so cause us to behave and to act in one way and not in another), and the rational foundation of theology and religion (concentrating his attacks on Deism, but also attacking the notions of providence, miracles, prophecy, the immortality of the soul, etc.).
Thus, reason came away a bit hurt from the eighteenth century, especially because of Hume’s attack upon it (and upon Deism) and Theism. The following century, the nineteenth, basically begins with Friedrich Schleiermacher, with a theology that is based on feelings and emotions – and therefore takes its focus away from reason. That is the beginning of the so-called Liberal Theology.
São Paulo, May 10th, 2019.