But anything else would be supernatural. And Secular Humainism can't accept the supernatural into its philosophy.
What jar is saying is that the conditions at the Big Bang are so vastly different from present conditions that what we call matter might be incapable of existing. However the existent entities under those conditions would still be physical.
Take for instance a proton, something which is a fundamental component of any atom. A proton is actually a low-energy/temperature phenomena and not a universal particle.
Turn up the energy/temperature and it dissolves, not because it melts or anything, but because the physics required for it to exist only occurs at low temperatures/energies. At high energies a proton can't occur.
Similarly, back at the Big Bang things might have been so hot/energetic that no particle that we know could occur as a phenomena.
In addition to this fact even the word particle itself begins to lose meaning when space-time becomes very curved, such as near the Big Bang.
These are very subtle issues and to be fair require a good deal of familiarity with the subject, as they involve two very difficult fields called "non-perturbative QFT" and "QFT in curved spacetimes" and ultimately a much more difficult subject called "Quantum Gravity".
This message has been edited by Son Goku, 01-26-2006 12:44 PM