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                                                                       Exhibit 5

                          [LETTERHEAD OF ASHLAND INC.]


                                                              September 7, 2001


Ashland Inc.
50 E. RiverCenter Boulevard
Covington, KY  41012


Dear Sirs:

     As Vice President and General Counsel of Ashland Inc., a Kentucky
corporation (the "Company"), I have examined and am familiar with the Second
Restated Articles of Incorporation of the Company, as amended, and the By-laws
of the Company, as amended. I am also familiar with the corporate proceedings
taken by the Board of Directors to authorize the Registration Statement on Form
S-3 (the "Registration Statement") being filed by the Company on the date hereof
with the Securities and Exchange Commission under the Securities Act of 1933
(the "Securities Act") with respect to $600,000,000 aggregate initial offering
price of unsecured debt securities, which may be either senior or subordinated
debt securities (the "Debt Securities"), shares of cumulative preferred stock,
without par value (the "Preferred Stock"), depositary shares (the "Depositary
Shares"), shares of common stock, par value $1.00 per share (the "Common Stock")
and warrants to purchase Debt Securities, Preferred Stock or Common Stock (the
"Warrants"), for issuance from time to time pursuant to Rule 415 under the
Securities Act.

     In connection with the foregoing, I have examined originals, or copies
certified or otherwise identified to my satisfaction, of such documents,
corporate records and other instruments as I have deemed necessary or
appropriate for the purpose of this opinion.

     Based upon the foregoing, I am of the opinion that:

     1. When the Debt Securities have been duly authorized by appropriate
corporate authorization and executed, authenticated and delivered against
payment therefor, such Debt Securities will be validly issued and will
constitute binding obligations of the Company in accordance with their terms,
subject to applicable bankruptcy, reorganization, moratorium or similar laws
affecting creditors' rights generally from time to time in effect.


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Ashland Inc.
September 7, 2001
Page 2


     2. When the Preferred Stock, the Common Stock and the Depositary Shares
have been duly authorized by appropriate corporate authorization and when
issued, such Preferred Stock, Common Stock, and Depositary Shares will be
validly issued, fully paid and nonassessable.

     3. When the Warrants have been duly authorized by appropriate corporate
authorization and executed, countersigned and delivered against payment
therefor, such Warrants will be validly issued and will constitute binding
obligations of the Company in accordance with their terms, subject to applicable
bankruptcy, reorganization, moratorium or similar laws affecting creditors'
rights generally from time to time in effect.

     I know that I am referred to under the heading "Legal Matters" in the
Registration Statement, and I consent to such use of my name in the Registration
Statement and to the use of this opinion for filing as an exhibit to the
Registration Statement.

                                                              Very truly yours,



                                                              David L. Hausrath

