Christian "purpose" and "meaning" in life.

[Mudhammam]

I am not arguing that intentionality is not a feature found in reality. I do say that theories based on ontological naturalism (or just naturalism) are inconsistent with the fact that intentionality is part of our reality.

Since the time of Francis Bacon, natural science has proceeded on the assumption that all physical processes can be fully described using only two the four Aristotelian causes: efficient and material cause. In biology, this culminates in Richard Dawkins‘s book, “The Blind Watchmaker”. Evolutionary processes do not seek desired ends any more than the planets do in their revolutions around the sun. To have a consistent worldview, the naturalist must apply the same rules to all evolved features regardless of whether it is the horn of the rhino or human prefrontal cortex.

Ironically, I think you're confused as to the purpose of reductionism. There's no inconsistency in describing, take for example, love as a biochemical formula but still acknowledging that reducing the emotion to an equation is not sufficiently descriptive of the subjective sensation itself. That's the job of great works of romance. Likewise, you're conflating two levels of understanding, two different modes of language, one for the microscopic and one for the macroscopic. The former often serves to inform the nature of the latter; it doesn't negate it. I don't cease to exist, nor does my meaning, because I'm a being made of atoms and not "soul stuff," because love is a biochemical reaction and not magic, though it can feel magical to me. Denying intentionality in the Universe is only denying that what deceptively passes to us as intentionality and intelligence is that which the lawful processes of nature have produced over time, using natural selection as the vehicle. You're saying that the process itself is an intentional and intelligent process, and reductionism denies this, as that is what the evidence suggests--the extinction rate alone seems to discredit the notion. Then of course, you can point to the never ending examples of deformities and mutations and collisions of debris and other general chaos that serves no apparent creative purpose; actually just the opposite. What you perceive to be the creative forces in nature is what probably drives you to your unjustified assertion that an invisible hand attached to an invisible head with an apparently enormous invisible brain is pulling the strings.

As it relates to this this thread, meaning is a particular kind of intentionality. The atheistic claim is that life can have meaning without God. Leaving aside whether the ultimate source of meaning comes from a Supreme Being or not, the naturalist that a says his life has meaning cannot do so without making reference to the very intentionality that he denies.

It's a very different thing to say, "Contributing to the advancement of mankind and the planet gives me meaning" than it is to say, "the meaning of the Universe is that evolution on the planet Earth would bring forth a person named PickupShonuff would who create his own meaning." You're conflating apparent design in the Universe--which comes about through chance and necessity, for reasons or not that regardless no one quite fully understands--with design that humans come up with, which from our perspective seem to be choices of purpose that are very dear to us. I'm sure when the chimpanzee in the rain forest is beating a rock against a nut to crack it open, it appears very purposeful to the chimp mind as well, however its brain processes whatever might be akin to our human conception of intentionality. Highly evolved brains, chiseled by hundreds of millions of years of natural selection do this. Not rocks. Not atoms.

Sure you do. Here I am talking about purpose, a second type of intentionality. Purpose is the final end someone seeks to achieve. If the final end endures without ceasing, I call that eternal. For example, the Great Commission charges Christians with the specific purpose of helping win souls for the Kingdom, which if true, produces permanent results with never-ending repercussions. If atheism is true, then humans accomplishments have no lasting value. Buildings decay. Monuments topple. Legacies wither. The sun explodes and everyone dies. Confronted with the vanity of earthly existence, the atheist cannot hope that the purpose for which they live has any value beyond the immediate future. In contrast to this, Christians can have such hope.

I don't think anyone seriously links their decision to get out of bed in the morning and find something that brings fulfillment to their lives with the death of the sun in 5 billion years or whatever it is. You're appealing to the age-old anthropomorphic desire that the Universe must serve your purposes on Earth. Does the dolphin take comfort that within a few years it will swim in a pure blue lake made of Jesus' tears? The brain evolved, some would say miraculously in the truest sense of against all odds, to do incredible things; question authority, develop science, send robots into space, fight disease and poverty. Sitting around and fantasizing, hoping the wish becomes reality without doing any of the hard work, is not one of them.