WASHINGTON--President Nixon's economic advisers told Congress Monday "it would be a delusion" to attempt to solve the nation's domestic problem by levying heavier taxes on the wealthy.

Banking on what one congressman called their "hour of happiness" resulting from the best economic news of the Nixon administration, the advisers predicted continued economic expansion, lowered inflation and they said unemployment can be cut to "the neighborhood of 5 per cent" by the end of the year.