Is the universe contingent? Is it ever valid to infer from part to whole? The short answers are yes and yes. But, please read on.
It is regularly claimed that to invoke the principle of sufficient reason in cosmological arguments like Leibniz’s argument for God’s existence is to commit the fallacy of composition, to “mistakenly assume that a characteristic of some or all the individuals in a group is also a characteristic of the group itself, the group ‘composed’ of those members.”
In his recent book, Five Proofs for the Existence of God, Dr. Edward Feser responds to this objection. He writes:
Not every inference from part to whole commits a fallacy of composition. Whether such a fallacy is committed depends on what sort of feature of the parts we are reasoning about.
In other words, the crucial question is whether the relevant property is one which must be true of the whole if it is true of all the parts. Feser offers two examples to illustrate his point. First, he considers the property of weight, writing, “If each stone in a certain collection of stones weighs less than an ounce, it doesn’t follow that the entire collection weighs less than an ounce.” Obviously, it would be invalid to infer that because each part weighs less than an ounce, the whole must also weigh less than an ounce. Second, he notes that the same form of reasoning is valid with regard to the property of color:
But where color (for example) is concerned, we can validly reason from the parts to the whole. If each Lego block in a pile of Lego blocks is red, then any object we make out of those blocks will also be red.
Feser then argues that contingency, the property with which the PSR is concerned, is like color, not weight. He says,
Take any contingent thing—a stone, a Lego block, a tree, a human being, whatever. A collection of three stones is obviously no less contingent than a single stone is, and a collection of three hundred or three million stones is obviously no less contingent than the collection of three stones.
It is quite silly to pretend, then, that when we get to the collection of all the stones there are, or all the contingent things there are, we might somehow suddenly have something that is not contingent.
Feser’s argument seems simple and obvious to me. A set of red things is, itself, red. A set of contingent things is, itself, contingent.
What do you think? Is the universe contingent or not? Tell me about it in the comments.
 The principle of sufficient reason (PSR) holds that there is an explanation for the existence of anything that does exist and for its having the attributes it has. (Feser, Edward. Five Proofs of the Existence of God (p. 161). Ignatius Press. Kindle Edition.)
 Feser, Edward. Five Proofs of the Existence of God (p. 155). Ignatius Press. Kindle Edition.
 Ibid., p. 155.
 Ibid., p. 156.
 Contingency refers to dependent existence, existence which requires a sufficient reason.
 Feser, p. 156.
 Ibid., p.156.