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                                                                     EXHIBIT 8.1

                                December 7, 2000



American General Corporation
2929 Allen Parkway
Houston, Texas  77019-2155

Ladies and Gentlemen:

         We have acted as counsel to American General Corporation, a Texas
corporation ("American General"), and American General Capital III, a Delaware
statutory business trust (the "Trust") in connection with the registration
statement under the Securities Act of 1933, as amended, of American General and
the Trust (and other trusts) on Form S-3 (Registration Nos. 333-40583, et. seq.)
filed with the Securities and Exchange Commission (the "Commission") and
declared effective by the Commission on February 10, 1998 (as amended, the
"Registration Statement"). In that connection, reference is made to a prospectus
dated February 10, 1998 (the "Prospectus") constituting a part of the
Registration Statement, relating to, among other things, junior subordinated
debentures of American General, and a prospectus supplement to the Prospectus
dated November 30, 2000 (the "Prospectus Supplement") describing the 8.05% Trust
Preferred Securities of the Trust (the "Preferred Securities") and the 8.05%
Junior Subordinated Debentures due 2049 of American General (the "Junior
Subordinated Debentures"). Capitalized terms not otherwise defined herein have
the meaning specified in the Prospectus and the Prospectus Supplement.

         We have examined the Prospectus, the Prospectus Supplement, and such
other documents and corporate records as we have deemed necessary or appropriate
for purposes of this opinion, and we have assumed that the Junior Subordinated
Debentures and the Preferred Securities will be issued in full compliance with
the operative documents described in the Prospectus and the Prospectus
Supplement.

         Based on the facts and assumptions contained in the Prospectus
Supplement, in our opinion (i) the Trust will be classified for United States
federal income tax purposes as a grantor trust and not as an association taxable
as a corporation, (ii) the Junior Subordinated Debentures will be classified for
United States federal income tax purposes as indebtedness of American General,
and (iii) the statements of legal conclusion set forth under the heading
"Certain United States Federal Income Tax Consequences" in the Prospectus
Supplement reflect our opinions with respect to the


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American General Corporation
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December 7, 2000


material United States federal income tax consequences of the ownership and
disposition of the Preferred Securities.

         We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and the reference to this Firm in the section captioned
"Certain United States Federal Income Tax Consequences" in the Prospectus
Supplement. In giving this consent, we do not thereby admit that we come within
the category of persons whose consent is required under Section 7 of the
Securities Act of 1933, as amended, or the rules and regulations of the
Commission thereunder.


                                             Very truly yours,




                                             VINSON & ELKINS L.L.P.