Evolution by natural selection explains the appearance of design in living things without any need for a designer, so the traditional design argument is simply obsolete.

Why people find it persuasive

Darwin showed that complex, apparently purposeful biological structures can arise through blind variation and non-random selection over long timescales, no mind required. Richard Dawkins's The Blind Watchmaker (1986) makes the case vividly: the eye and the wing look designed, but cumulative selection alone builds them. If nature can generate all the appearance of design theists cite as evidence, the argument from design collapses.

Important distinctions

• • Design arguments about biological complexity (Paley's watch) versus design arguments about cosmic fine-tuning (physical constants)
• • Evolution as a mechanism operating within an already-existing universe versus the origin of that universe's laws and constants
• • Evolution explaining the diversification of life versus the origin of life (abiogenesis) itself
• • Evolution as incompatible with any designer versus evolution as the means a designer might use
• • Undirected in the sense of unguided by immediate biological feedback versus undirected in the stronger metaphysical sense of purposeless

Christian response

• • Evolution by natural selection is well-supported science and directly answers Paley's specific nineteenth-century version of the design argument, which inferred a direct designer from biological complexity by analogy to a watch found on a heath. Darwin genuinely displaced that particular inference for biological structures, and most contemporary theistic philosophers, including Alvin Plantinga and Francis Collins (former head of the Human Genome Project and author of The Language of God, 2006), accept evolution as the actual historical mechanism God used, not as a rival to theism.
• • This means the classical Paley-style biological design argument is largely superseded among sophisticated theists, but the contemporary design conversation has moved to different terrain: cosmic fine-tuning of physical constants (the strength of gravity, the cosmological constant, the ratio of electromagnetic to gravitational force) required for any life-permitting universe at all, which evolution does not touch because evolution presupposes a universe with stable chemistry and physics already in place for it to operate in.
• • Evolution also does not explain the origin of life itself (abiogenesis), the transition from non-living chemistry to the first self-replicating organism, which remains a genuinely open scientific question; philosopher of biology Stephen Meyer, in Signature in the Cell (2009), argues the information content of DNA at life's origin still calls for explanation, though this argument (associated with the intelligent design movement) is contested by most working biologists and should not be overstated as a consensus scientific gap.
• • Even granting evolution fully as the mechanism, 'undirected' in the everyday biological sense (no immediate goal-directed feedback loop steering individual mutations) is a different claim from 'undirected' in the stronger metaphysical sense of being ultimately purposeless; a theist can consistently hold that God established laws and initial conditions such that evolution would reliably produce the outcomes he intended, similar to how a novelist can use a stochastic process within a story without the story being purposeless. Philosopher of science Elliott Sober has noted this is a coherent, non-contradictory position, whatever one thinks of its plausibility.
• • So the objection correctly retires one specific historical argument (Paley's watch) but does not touch the arguments many contemporary theistic philosophers actually rely on, which concern the existence and fine-tuning of the cosmos evolution operates within, not the mechanism of biological diversification itself.

Christian counterresponse

The relocation is principled rather than ad hoc: fine-tuning is not a residual unexplained biological mechanism awaiting a future Darwin, it is a distinct, independently discovered feature of fundamental physics (the values of the constants themselves), known through advancing physics rather than despite it, so it is not simply the same argument retreating to a smaller remaining space but a genuinely different line of evidence with its own literature and debate.