EXHIBIT 5.2

        [LETTERHEAD OF MENDELSOHN ROSENTZVEIG SCHACTER APPEARS HERE]

February 4, 1999

Autodesk, Inc.                          9066-9854 Quebec Inc.
111 McInnis Parkway                     1000 Sherbrooke St. West
San Rafael, California                  27th floor
94903, U.S.A.                           Montreal, Quebec
                                        H3A 3G4

9066-9771 Quebec Inc.
1000 Sherbrooke St. West
27th floor
Montreal, Quebec
H3A 3G4

Ladies and Gentlemen:

RE: REGISTRATION STATEMENT ON FORM S-4

We have examined the Registration Statement on Form S-4 to be filed by 
Discreet Logic Inc. ("Discreet"), Autodesk, Inc. ("Autodesk"), 9066-9854
Quebec Inc. and 9066-9771 Quebec Inc. with the United States Securities and
Exchange Commission on or about this date (the "Registration Statement") in
connection with the registration under the United States Securities Act of
1933, as amended, of shares of Common Stock of Autodesk, par value US$0.01 per
share (the "Autodesk Shares") and certain shares to be issued by the company
resulting from the amalgamation of Discreet, 9066-9854 Quebec Inc. and 9066-
9771 Quebec Inc. (the entity resulting from the amalgamation is referred to
herein as "New Discreet"). As your Canadian counsel in connection with the
transactions described in the Registration Statement (the "Transactions"), we
have examined the proceedings taken and are familiar with the proceedings
proposed to be taken by you in connection with the Transactions.

It is our opinion that upon conclusion of the proceedings being taken or 
contemplated by us, as your legal counsel, to be taken prior to the 
amalgamation of Discreet, 9066-9854 Quebec Inc. and 9066-9771 Quebec Inc., and
upon completion of the proceedings being or proposed to be taken in order to 
permit such amalgamation to be carried out in accordance with the Companies 
Act (Quebec), the amalgamation of Discreet, 9066-

 
                                      -2-
 
9854 Quebec Inc. and 9066-9771 Quebec Inc. will have been authorized by all 
necessary corporate action on the part of 9066-9854 Quebec Inc. and 9066-9771 
Quebec Inc.

We are also of the opinion that upon conclusion of the proceedings being taken 
or contemplated by us, as your legal counsel, to be taken prior to the issuance 
of the New Discreet Shares, and upon completion of the proceedings being taken 
in order to permit such transactions to be carried out in accordance with the 
applicable securities laws, the New Discreet Shares when issued and sold in the 
manner described in the Registration Statement, will be legally and validly 
issued, fully paid and non assessable. We express no opinion as to the shares to
be issued by Autodesk in the Transactions.

We are qualified to practice law in the Province of Quebec and do not express
any opinion with respect to the laws other than the laws currently in force in
the Province of Quebec and the federal laws of Canada applicable therein.

We consent to the use of this opinion as an exhibit to the Registration 
Statement, and further consent to the use of our name wherever appearing in the 
Registration Statement, including the Joint Proxy Statement/Prospectus 
constituting a part thereof, and any amendment thereto.

Yours very truly,

/s/ MENDELSOHN ROSENTZVEIG SHACTER
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MENDELSOHN ROSENTZVEIG SHACTER