Question: I've been reading about the billions of dollars in tax money that doesn't get to the government because so many people either don't file at all or file a dishonest return. What incentive is there for the rest of us to keep on paying?

Answer: The surface incentive is the compliance programs of the IRS. These include matching information reports against tax returns, special audits of questionable items or amounts, and general review of a random selection of returns in all income brackets.

But these programs are obviously not completely effective. The odds are at least fair that one can cheat and escape detection. So the basic incentive must be your own conscience.

By its very nature -- based on the theory of individual responsibility and to avoid a Gestapo-type police state -- our system of government depends on a high degree of voluntary compliance with all the laws, including the tax statutes.

The extensive survey that generated the news stories you have been reading shows that most Americans do in fact comply with the tax laws. The findings indicate that from 92 to 94 percent of income from legal sources was reported, and from 89 to 92 percent of the resulting tax liability was acknowledged.

As a result of the survey, the IRS is developing better procedures for discovering unreported income. Meanwhile, every taxpayer should use every legal means to keep his or her tax liability to a minimum; but when the bottom line is reached, pay every dollar legally due.

Q: Would it be advisable for me (and my husband) to file a gift tax return to cover a gift of $6,000 I made to my son last spring? If we don't file a gift tax return, in the event of my death might the gift be considered a loan and be deducted from a bequest to him provided in my will?

A: A gift tax return is required for any year in which total gifts to a single donee exceed $3,000. This is true despite the fact that there is an annual tax-free exclusion of $6,000 for gifts to any one donee if your husband consents to having the gift(s) considered one-half his (even though you provide the entire gift).

So you must file a gift tax return (on IRS Form 709) by Feb. 15, 1980 accounting for the $6,000 (plus any other gifts made to your son during the year). A joint gift tax return is not permitted; you file the return and your husband indicates his agreement for co-sponsorship by signing the "Consent of Spouse" on the return.

The second question has legal ramifications; I suggest you consult the attorney who prepared your will. However, my experience has been that the presumption usually goes in the other direction. That is, money given to a child will normally be considered a gift in the absence of evidence to the contrary (such as a loan agreement).

Incidentally, you may also be liable for a state gift tax return. Check with the local office of your state tax department for the rules in your home state.