Beatrice Arthur, who is probably going to become a star as Maude Findlay in the new CBS comedy series, nevertheless likes to depict herself as the perennial loser.

"Remember the year that Carol Burnett became famous singing, 'I'm In Love With John Foster Dulles'?" the attractive, dark-eyed, woman with frosty hair demanded in her penetrating voice. "Well, the year before, I came out with a song called 'I'm In Love With Sammy Snead'!"

Equity, the theatrical union, has a category that applies to performers who speak less than five lines. Miss Arthur claims she was the "most unemployed under five lines" actress in the business. When her old friend, Norman Lear, who produces All In the Family and who coaxed her into doing Maude, told her she was good for at least 13 weeks in the new series, Miss Arthur says she cried, "No more under fives!"

But the salty, lively fiftyish actress, who is married to film producer Gene Saks, insisted during a recent New York interview that her autobiography will derive its inspiration from her experience in the musical Mame, in which she appeared with Angela Lansbury.

"I had the role of Vera, and even though I won a Tony for it I always wore black," she recalled distastefully. "When the cast took its bows, I was always next to the last and always I was in black. Then Angie would come out to take her final star bow and she was dressed in gorgeous white. I said to myself, 'If I ever worked again, I'm coming down to take my bow in white'!"

Until Lear asked her to do a spin-off series from All In the Family about Edith Bunker's ultra-liberal, unconventional, well-heeled Westchester County cousin, Miss Arthur had worked diligently if not with too much fanfare in TV, the theater, and a few films.

"Freddy Silverman, CBS vice president in charge of programming called Norman after my first appearance on Family and said, 'Who is that girl?' He meant me. Imagine, 'Who is that girl?' And after 20 years in show business!"

A native New Yorker who grew up during the depression in Cambridge, Md., where her father operated a store, Miss Arthur attended school in Liberty, Pa., and eventually returned to New York for what she hoped would be a brilliant theatrical career.

"Erwin Piscator, the drama coach, said he saw me as the 'classic German heroine' because of my height and voice. For a while, it seemed that all I could play was leading women. Then I thought I could sing at a time when every girl singer was trying to sing like Lena Horne. I bombed miserably as a singer, but Julius Monk said, 'Gee Bea, I think you should try comedy.'"

She first met Lear when she was in a shoestring off-Broadway review in 1954 and he was a comedy writer. "We were all starving together." Lear got her into the Gobel show just before it died. When he made All In the Family such a big success he immediately began trying to pressure her to make a guest appearance. She says she stoutly resisted.

"I might as well tell you that once my husband became a success (his most recent film: "Last of the Red Hot Lovers"), and I didn't have to worry where my next meal was coming from I decided to work only when I wanted to.

"I retreated to our lovely suburban New York home with our two youngsters and numerous dogs to garden, be a mother, and enjoy life. But Norman kept up his demands. Finally, I gave in. I was frightened...I'd been living among the trees and plants for so long I'd forgotten what the world of show business was like.

"I didn't know what or who Maude is supposed to be. I guess she's me. The writer spent some time with me in writing my first appearances in All In the Family. All my life, for example, I've fought against what I consider petty injustices. I once took a landlord to court because I felt he had wronged me. But to say that Maude is a present day 'Auntie Mame' is ludicrous.

"I am this lady who is representative of a lot of women who are unafraid to emphasize themselves. Of course I'm a liberated woman--that's old hat. I'm a hightly individualistic woman, but in a way I guess I'm reserved. For instance in the series I tell our maid, who is black, to call me 'Maude' but I would never think of calling her anything except 'Mrs.'"